1. Field of the Invention
The present invention relates to a water and oil repellent composition. The water and oil repellent composition of the present invention is excellent in storage stability, and particularly when applied to paper, it imparts excellent water resistance and sizing property of the paper. Further, when applied to natural leather or synthetic leather, it imparts excellent water resistance and oil resistance thereto.
2. Description of the Background
Heretofore, as a water and oil repellent for paper, an amine salt of a phosphate containing a polyfluoroalkyl group (hereinafter referred to as a R.sup.f) has been known, and it has been widely employed in a premixing method wherein it is incorporated during paper making an in a post treatment method wherein it is incorporated during immersion of sheeted paper. However, particularly when the post treatment method is employed, if the treatment is carried out at a high speed by means of a sizing press or a coater, there has frequently been a problem that the water resistance tends to be poor. Further, the water and oil repellent composed mainly of an amine salt of a phosphate containing an Rf group has had a problem that the storage stability is inadequate, and it undergoes a phase separation when stored for a long period of time. Further, there has been a problem such that the performance tends to be poor by an influence of the hardness of water to be used for e.g. dilution, by the presence of impurities or by other processing agents used together, or it forms a precipitate or gum-like substance, which may stain processing rolls.
As a composition for improving the dispersion stability of a water and oil repellent, a composition having a hydrocarbon type anionic surfactant incorporated to an amine salt of a phosphate containing a R.sup.f group (JP-A-64-6196) or a composition having a fluoroaliphatic hydrocarbon or chlorofluoroaliphatic hydrocarbon incorporated to an amine salt of a phosphate containing a R.sup.f group (JP-A-56-138197) has been proposed.
However, when such a conventional composition is applied to paper, a problem has been observed such that the water resistance is inadequate. Further, a problem has been observed such that the storage stability is inadequate, whereby it undergoes a phase separation during storage for a long period of time, or it undergoes phase separation also due to impurities or a processing agent used together.